This invention relates to film identification apparatus and more particularly to such apparatus for placing identifying indicia on photographic film.
The present invention, while of general application, is particularly well suited for applying identifying indicia to x-ray or other radiographic film. In many modern hospitals, for example, the problem of accurately correlating the identity of a patient with a particular x-ray photograph has become increasingly acute. Some of the early attempts to resolve this problem entailed the use of lead letters or symbols which were arrayed against the face of an x-ray cassette adjacent one of its edges. The film was then exposed either by the same x-ray machine used to photograph the patient or with a different x-ray machine. With the increasingly large number of x-rays taken in a given hospital, however, the task of assembling the individual letters or symbols to provide such patient identification became correspondingly burdensome and expensive, and the procedures used for accomplishing this were subject to many opportunities for both human and mechanical error.
More recently, attempts to resolve the film identification problem made use of typed cards on an electroluminescent panel. The panel and card assembly was inserted in a corresponding opening in one edge of the cassette such that, upon the illumination of the panel, the information on the card was reproduced on the film.
Film identification apparatus of the foregoing type have exhibited several disadvantages. As an illustration, several of the apparatus previously employed used an electroluminescent panel which, to provide the desired illumination, needed to be too thin to have sufficient structural rigidity to withstand repeated insertion and withdrawal in the openings of successive cassettes. In an effort to alleviate this problem, certain types of such prior apparatus enclosed the panel within a rigid tongue member which was inserted into the opening in the cassette together with the typed card and the panel itself. However, such a tongue member not only required an unnecessarily large opening, but it also was not suitable for use with many of the thinner types of cassettes. In addition, the comparatively massive tongue member frequently interfered with the legibility of the indicia formed on the film and had other disadvantages.